Iv noticed over the last few weeks that my OP3 does no longer trigger notifications on airdroid. It connects as usual, and im able to send sms from the app and webapp however it does not know a sms coming in and I have to always hit refresh for it to show up. Thinking it was a firmware update on my op3 that caused it but im not sure.

I have uninstalled and reinstalled airdroid on my phone and windows pc but it did not solve the issue. I also double checked the permissions and its all enabled.

I had the same problem, and I had to follow the instructions provided in the link you posted. I had already enabled notifications previously, so what happened that I had to enable them again? Was it the upgrade which wiped some data? I hope I don't have to keep doing this. Cheers, Dominic